$def with (form_ref)

$# Forms will bind the "enter" key to the first submit button ; in the case
$# we show the delete button for librarians, that becomes the first submit
$# button! So we duplicate the save button here to make sure that it's always
$# the default "enter" action.
<button type="submit" class="hidden" name="_save" form="$form_ref" tabindex="-1"></button>